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UM10503
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User manual
Rev. 2.1 — 10 December 2015
541 of 1441
NXP Semiconductors
UM10503
Chapter 21: LPC43xx/LPC43Sxx General Purpose DMA (GPDMA)
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Source and destination burst sizes, 16 transfers.
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Next LLI address, 0x2000 0020.
A chain of descriptors is built up, each one pointing to the next in the series. To initialize
the DMA stream, the first LLI, 0x2000 0000, is programmed into the DMA Controller.
When the first packet of data has been transferred the next LLI is automatically loaded.
The final LLI is stored at 0x2000 0070 and contains:
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Source start address 0x2000 1200.
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Destination address set to the destination peripheral address.
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Transfer width, word (32-bit).
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Transfer size, 3072 bytes (0xC00).
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Source and destination burst sizes, 16 transfers.
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Next LLI address, 0x0.
Because the next LLI address is set to zero, this is the last descriptor, and the DMA
channel is disabled after transferring the last item of data. The channel is probably set to
generate an interrupt at this point to indicate to the ARM processor that the channel can
be reprogrammed.